Encrypted data reproducing transmitting and processing method and apparatus with separately encrypted control data

ABSTRACT

A data reproducing apparatus high in security against unauthorized duplication. A drive 20 includes a first CSS encoder 21 for performing first encryption processing on picture data etc reproduced from an optical disc D and a second CSS encoder 22 for performing second encryption processing different from the first encryption processing on the media type information of the optical disc D. The drive transmits the so-processed data or information. A data processing device 30 performs decryption processing on the transmitted picture data etc and on the media type information by respective independent decoders. The data processing apparatus detects the copyright control information from the picture data etc and performs reproduction limitation or recording limitation on the picture data etc.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a data reproducing method and apparatus, adata transmitting method, a data transmitting system, and a dataprocessing method and apparatus for protecting the copyright of datarecorded on a recording medium or transmitted over a transmissionmedium, and for safeguarding against unauthorized duplication.

2. Description of the Related Art

Recently, with coming into widespread use of digital contents, such asInternet or digital video discs, infringements of the digital contentsby unauthorized duplication of the digital contents, frequently giverise to a problem.

For coping with this problem, there has recently been proposed a methodof prohibiting unauthorized copying of picture or music data purveyed ina stored state on a recording medium or using a network as atransmission medium by burying the copyright information in the data bywatermark processing.

The watermark processing is the processing of burying the information asa noise in a perceptually non-crucial portions present im the picture ormusic data, that is in the non-redundant portions with respect to themusic or the picture. The copyright information, buried in the pictureor music data by such watermark processing, can scarcely be removed,while it can be retrieved even after filtering or data compression.

For overcoming the above problem, it has been proposed to bury thewatermark processing in picture data etc or to encrypt data beingrecorded or transmitted to prohibit unauthorised duplication. Byencrypting the recorded or transmitted data, unauthorized duplicationcannot be made unless the encrypting algorithm is decoded.

FIG. 1 shows a conventional optical disc reproducing device exploitingthe above-mentioned watermark processing and encryption.

The conventional optical disc reproducing device 100, shown in FIG. 1,is applied to, for example, a personal computer.

This optical disc reproducing device 100 includes an optical disc drive101, a data processing device 102for doing data processing on picturedata etc read out from the optical disc drive 101, and a transmissionline 103 for interconnecting the optical disc drive 101 and the dataprocessing device 102.

In a data area of an optical disc D is recorded picture data on movingor still pictures or speech data on music or speech. These data arepreviously compressed in accordance with the MPEG system. On the picturedata, the copyright information is superimposed by the above-mentionedwatermark processing.

The copyright information, superimposed on the picture data, may beexemplified by the following copyright control information:

That is, there are superimposed on the picture data “copy free”,specifying that picture or music data recorded on the recording mediumor transmitted can be copied, “one copy”, specifying that only onecopying operation is possible, “no more copy” specifying that data hasbeen copied from the above “one copy” data, or “never copy” specifyingthat copying cannot be permitted. The reproducing device or therecording device, which has detected this copyright control information,limits reproduction or recording on the picture or music data.

The compressed picture data or compressed speech data, recorded on thisoptical disc D, is encrypted by a predetermined encrypting key.

On the optical disc D, there is recorded the media type information ofthis optical disc D, along with the above-mentioned picture data oraudio data. This media type information is the information specifyingwhether the optical disc is the read-only ROM disc or a recordable RAMdisc.

From this optical disc D, the above media type information as well asthe compressed picture or audio data is read out by the optical discdrive 101.

The optical disc drive 101 sends the read-out compressed picture data,compressed speech data and the media type information over thetransmission line 103 to the data processing device 102. The datatransmitted on the transmission line 103 is transmitted after beingencrypted by the so-called contents scramble system (CSS).

If the present optical disc reproducing device 100 is applied to, forexample, a personal computer, the transmission line 103 is connected bythe bus line.

The data processing device 102 includes a CSS decoder 104, an MPEGdecoder 105, a media type decoder 106, watermark (WM)detection/re-encoding unit 107, an output controller 108, and switches111, 112.

The data processing device 102 is enclosed in, for example, a data cardetc loaded on a personal computer.

The CSS decoder 104 is fed with the compressed picture or audio data andthe media type information, transmitted in the encrypted form, andexecutes decryption using a predetermined encryption key. If decryptionis not made using the correct decryption key, the ensuing processingcannot be effectuated. If decryption is done using the correctencryption key, this CSS decoder 104 sends picture data and audio datato the MPEG decoder 105, while sending the media type information to themedia type decoder 106.

The MPEG decoder 105 expands the compressed picture and speech data. Theexpanded picture data is sent to the watermark (WM)detection/re-encoding unit 107, while the expanded speech data isoutputted via switch 111 to outside.

The media type decoder 106 decodes the media type information sent fromthe CSS decoder 104 to detect the information on whether the opticaldisc D reproduced by the optical disc drive 101 is a ROM disc or a RAMdisc, and sends the detected information to the output controller 108.

The watermark (WM) detection/re-encoding unit 107 detects the copyrightcontrol information, superimposed on the picture data by watermarkprocessing. The detected copyright control information is “copy free”,“one copy”, “no more copy” or “never copy”, as described above. Thewatermark (WM) detection/re-encoding unit 107 sends the detectedcopyright control information to the output controller 108. If, as aresult of detection of the copyright control information, the watermark(WM) detection/re-encoding unit 107 has detected “one copy”, itre-encodes the copyright control information superimposed on the picturedata by watermark processing to change the copyright control informationto “no more copy” and outputs the result to outside via switch 112. If,as a result of detection of the copyright control information, thewatermark (WM) detection/re-encoding unit 107 has detected theinformation other than “one copy”, it outputs the detected result tooutside via switch 112 without performing the re-encoding.

The output controller 108 performs on/off control of the switch 111 andthe switch 112, based on the information sent from the media typedecoder 106 and the watermark (WM) detection/re-encoding unit 107.Specifically, if the optical disc D is the ROM disc and the copyrightcontrol information is “no more copy”, and if the optical disc D is theRAM disc and the copyright control information is “one copy”, the outputcontroller 108 assumes that data recorded on the optical disc D has beenduplicated illicitly, and accordingly controls the switches 111, 112 tooff states.

In the conventional optical disc reproducing device 100, as describedabove, it is possible to encrypt data transmitted between the opticaldisc drive 101 and the data processing device 102 to preventunauthorized duplication and to manage control for halting thereproduction of the illicitly duplicated optical disc D using thecopyright control information.

In the above-described conventional optical disc reproducing device 100,the processing of superimposing the copyright control information bywatermark processing is performed on base-band picture data prior toMPEG encoding. There are occasions, however, wherein the copyrightcontrol information is superposed on an elementary stream prior to MPEGencoding. In such case, the data processing device 102 of the opticaldisc reproducing device 100 is configured so that the watermark (WM)detection/re-encoding unit 107 detects the copyright control informationbased on the compressed picture data prior to MPEG decoding and theswitch 111 is provided between the CSS decoder 104 and the MPEG decoder105.

It is feared that an unauthorized reproducing device 202 shown in FIG. 3is provided in the above-described conventional optical disc reproducingdevice 100. This unauthorized reproducing device 202 acquires inputsignals from the transmission line 103 between the optical disc drive101 and the data processing device 102 to effect decryption by anillicitly prepared CSS decoder 204. An MPEG decoder 205 expands picturedata obtained from this illicitly prepared CSS decoder 204 to outputvideo and audio data.

That is, in the conventional optical disc reproducing device 100,picture data, speech data and media type information are transmittedafter encryption by a sole algorithm. Thus, unauthorized duplicationoccurs on decoding this sole algorithm.

In consideration that the unauthorized reproducing device 202 isfabricated by decoding the sole encrypting algorithm, a datatransmission system with higher security has been a desideratum.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a datareproducing method and apparatus, a data transmitting system, a datatransmitting method and a data processing method and apparatus havinghigh security against unauthorized duplication of transmitted orrecorded data.

In one aspect, the present invention provides a data reproducingapparatus including reproducing means for reproducing data recorded on arecording medium, first encryption means for performing first encryptionprocessing on the data reproduced by the reproducing means, secondencryption means for performing second encryption processing differentfrom the first encryption processing on at least control data concerningcopyright control processing of the data reproduced by the reproducingmeans and transmission means for transmitting the data encrypted by thefirst encryption means and the second encryption means.

This data reproducing apparatus performs different encoding processingon control data.

In another aspect, the present invention provides a data reproducingapparatus including reproducing means for reproducing data recorded on arecording medium;

encryption means for encrypting the data reproduced by the reproducingmeans and control data relevant at least to copyright control processingof the data, transmission means for transmitting data encrypted by theencrypting means to an external signal processing device, receptionmeans for receiving playback control data transmitted from the externalsignal processing device, the playback control data being the datatransmitted by the transmission means encrypted in a manner differentfrom the encrypting by the encrypting means and processed with copyrightcontrol processing, decrypting means for doing decrypting matched toencrypting of the playback control data received by the reception means,and control means for controlling the playback processing of thereproducing means based on the playback control data decrypted by thedecrypting means.

This data reproducing apparatus also performs different encodingprocessing on control data.

In a further aspect, the present invention provides a data processingapparatus including reception means for receiving data processed withfirst encrypting processing and control data at least relevant tocopyright control processing of the data and which is encrypted bysecond encrypting processing different from the first encryptingprocessing, the data and the control data being transmitted from anexternal device, first decrypting means for doing first decryptingprocessing, matched to the first encrypting processing, on the datareceived by the reception means, second decrypting means for doingsecond decrypting processing, matched to the second encryptingprocessing, on the data received by the reception means, outputtingmeans for outputting data decrypted by the first decrypting means, andcontrol means for doing copyright control processing of the dataoutputted by the outputting means, based on at least the control datadecrypted by the second decrypting means, for controlling outputtingprocessing of the outputting means.

This data processing apparatus performs different encoding processing oncontrol data.

In a further aspect, the present invention provides a data processingapparatus including reception means for receiving data and control dataat least relevant to copyright control processing of the data, the dataand the control data being encrypted and transmitted in this encryptedform from an external device, decrypting means for performing matcheddecrypting processing on the data and the control data received by thereception means, outputting means for outputting data decrypted by thedecrypting means, control means for doing copyright control processingof the data outputted by the outputting means, based on at least thecontrol data decrypted by the decrypting means, for generatingtransmission control data controlling transmission processing of thedata transmitted from the external device, encrypting means forperforming encrypting processing on the transmission control datagenerated by the control means, the encrypting processing beingdifferent from that on the data and control data received by thereception means and transmitting means for transmitting the transmissioncontrol data encrypted by the encrypting means to the external device.

This data processing apparatus performs different encoding processing oncontrol data.

In a further aspect, the present invention provides a data transmissionsystem including a data reproducing apparatus and a data processingapparatus, in which data reproduced from a recording medium by the datareproducing apparatus is transmitted to the data processing apparatus,the transmitted data is processed in a predetermined manner by the dataprocessing apparatus and in which the processed data is outputted,. Thedata reproducing apparatus includes reproducing means for reproducingdata recorded on a recording medium, first encryption means forperforming first encryption processing on the data reproduced by thereproducing means, second encryption means for performing secondencryption processing different from the first encryption processing onat least control data concerning copyright control processing of thedata reproduced by the reproducing means, and transmission means fortransmitting the data encrypted by the first encryption means and thesecond encryption means. The data processing apparatus includesreception means for receiving data processed with first encryptingprocessing and control data at least relevant to copyright controlprocessing of the data and which is encrypted by second encryptingprocessing different from the first encrypting processing, the data andthe control data being transmitted from an external device, firstdecrypting means for doing first decrypting processing, matched to thefirst encrypting processing, on the data received by the receptionmeans, second decrypting means for doing second decrypting processing,matched to the second encrypting processing, on the data received by thereception means, outputting means for outputting data decrypted by thefirst decrypting means, and control means for doing copyright controlprocessing of the data outputted by the outputting means, based on atleast the control data decrypted by the second decrypting means, forcontrolling outputting processing of the outputting means.

This data transmission system performs different encoding processing oncontrol data.

In a further aspect, the present invention provides a data transmissionsystem including a data reproducing apparatus and a data processingapparatus. The data reproducing apparatus includes reproducing means forreproducing data recorded on a recording medium, including encryptionmeans for encrypting the data reproduced by the reproducing means andcontrol data of the data relevant at least to copyright controlprocessing, transmission means for transmitting data encrypted by theencrypting means to an external signal processing device, receptionmeans for receiving playback control data transmitted from the signalprocessing device, the playback control data being the data transmittedby the transmission means, the transmitted data being processed withcopyright control processing, decrypting means for doing decryptingmatched to encrypting of the playback control data received by thereception means, and control means for controlling the playbackprocessing of the reproducing means based on the playback control datadecrypted by the decrypting means. The data processing device includesreception means for receiving data and control data at least relevant tocopyright control processing of the data, the data and the control databeing encrypted and transmitted in this encrypted form from an externaldevice, decrypting means for performing matched decrypting processing onthe data and the control data received by the reception means,outputting means for outputting data decrypted by the decrypting means,control means for doing copyright control processing of the dataoutputted by the outputting means, based on at least the control datadecrypted by the decrypting means, for generating transmission controldata controlling the transmission processing of the data transmittedfrom the external device, encrypting means for performing encryptingprocessing on the transmission control data generated by the controlmeans, the encrypting processing being different from that on the dataand control data received by the reception means, and transmitting meansfor transmitting the transmission control data encrypted by theencrypting means to the external device.

This data transmission system performs different encryption processingon control data.

The data reproducing method according to the present inventionreproduces data recorded on the recording medium, performs firstencryption processing on the reproduced data, while performing secondencryption processing different from the first encryption processing andtransmitting the encrypted data and control data.

This data reproducing method performs different encryption processing oncontrol data.

In a further aspect, the present invention provides a data reproducingmethod including reproducing data recorded a recording medium,performing first encryption processing on the reproduced data,performing second encryption processing, different from the firstencryption processing, on at least control data for copyright controlprocessing of the reproduced data, and transmitting the encrypted dataand control data.

This data reproducing method similarly performs different encryptionprocessing on control data.

In a further aspect, the present invention provides a data processingmethod including receiving data subjected to first encryption processingand at least control data of the data subjected to second encryptionprocessing different from the first encryption processing, the data andthe control data being subsequently transmitted from an external device,performing first decryption processing matched to the first encryptionprocessing on the received data, performing second decryption processingmatched to the second encryption processing on the received controldata, performing at least copyright control processing based on controldata subjected to the second decryption processing to control outputprocessing.

This data processing method similarly performs different encryptionprocessing on control data.

In a further aspect, the present invention provides a data processingmethod including receiving data and at least its control data relevantto copyright control processing, the data and the control data beingencrypted and transmitted in this encrypted form from an externaldevice, performing matched decryption processing on the received dataand control data, outputting decrypted data, performing copyrightcontrol processing on the outputted data, based at least on thedecrypted control data, to generate transmission control datacontrolling transmission of data from the external device, performingencryption processing different from that performed on the received dataand control data on the generated transmission control data, andtransmitting the encrypted transmission control data to the externaldevice.

This data processing method similarly performs different encryptionprocessing on control data.

In a further aspect, the present invention provides a data transmissionmethod in which a transmitting side transmits data reproduced from arecording medium via a transmission medium and in which a reception sideperforms pre-set processing on transmitted data to output the processeddata, wherein the transmitting side reproduces the data recorded on therecording medium, processes the reproduced data with first encryption,processes control data at least relevant to copyright control processingof the data with second encryption different from the first encryption,and transmits encrypted data and control data over a transmissionmedium, with the reception side receiving the transmitted data andcontrol data, performing first decryption processing matched to thefirst decryption processing on the received data, and performing seconddecryption processing matched to the second decryption processing on thereceived control data. The decrypted data is outputted, and copyrightcontrol processing for the outputted data is performed based on at leastthe control data subjected to the second decryption processing.

This data transmitting method performs different encryption processingon control data.

In yet another aspect, the present invention provides a datatransmission method in which a transmitting side transmits datareproduced from a recording medium via a transmission medium and inwhich a reception side performs pre-set processing on transmitted datato output the processed data, wherein the transmitting side reproducesthe data recorded on the recording medium, processes the reproduced dataand at least control data of the reproduced data relevant to copyrightcontrol processing with encryption, transmits the encrypted data andcontrol data over a transmission medium to the reception side, receivesthe playback control data encrypted and transmitted in this encryptedform from the reception side, performs decryption processing matched toencryption processing of the received playback control data, andcontrols playback processing based on the decrypted playback controldata sent from the reception side, and wherein the reception sidereceives the transmitted data and the control data, performs matcheddecryption processing on the received data and control data, outputs thedecrypted data, performs copyright control processing of the outputteddata based on at least the decrypted control data, generatestransmission control data controlling the transmission of data from thetransmitting side, performs decryption processing different from thatperformed on the received data and control data on the generatedtransmission control data and transmits the encrypted transmissioncontrol data to the transmitting side.

In the data reproducing apparatus, data processing apparatus, datatransmitting system, data reproducing method, data processing method,and data transmitting method and apparatus, data and control datatherefor are transmitted, while the control data is encrypted in adifferent manner from the data. This raises security with respect tounauthorized duplication.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a conventional optical disc reproducingdevice adapted for performing watermark processing for encryption andcopyright protection of transmitted data.

FIG. 2 is a block diagram of another conventional optical discreproducing device adapted for performing watermark processing forencryption and copyright protection of transmitted data.

FIG. 3 is a block diagram of an unauthorized reproducing device forillicit duplication on the conventional optical disc reproducing deviceshown in FIGS. 1 or 2.

FIG. 4 is a block diagram of an optical disc reproducing deviceaccording to a first embodiment of the present invention.

FIG. 5 is a block diagram of an optical disc reproducing deviceaccording to a second embodiment of the present invention.

FIG. 6 is a block diagram of an optical disc reproducing deviceaccording to a third embodiment of the present invention.

FIG. 7 is a block diagram of an optical disc reproducing deviceaccording to a fourth embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, first to fourth embodiments of an opticaldisc reproducing device according to the present invention will beexplained in detail.

The optical disc reproducing device of the first to fourth embodiments,now explained, is made up of an optical disc drive, provided as anexternal device of a personal computer, and a data processing deviceloaded as, for example, a PC card of the personal computer. The opticaldisc device of the first to fourth embodiments reproduces the picturedata and speech data from the optical disc and transmits the picture andspeech data as digital data between the optical disc drive and the dataprocessing device to perform predetermined data processing.

Referring to FIG. 4, the first embodiment of the optical discreproducing device 1 is explained.

The optical disc reproducing device 1 of the present first embodiment ismade up of an optical disc drive 20 for reading out picture data orspeech data recorded on the optical disc D, a data processing device 30for doing data processing on the picture data etc read out from theoptical disc drive 20, and a bus 10 interconnecting the optical discdrive 20 and the data processing device 30.

In the data area of the optical disc D are recorded picture data formoving or still pictures and speech data on the music or the speech,after compression in accordance with the MPEG system. On the picturedata is superimposed the copyright control information by watermarkprocessing, as described above.

The copyright information, superimposed on the picture data, may beexemplified by the following copyright control information:

That is, there are superimposed on the picture data “copy free”,specifying that picture or music data recorded on the recording mediumor transmitted can be copied, “one copy”, specifying that only onecopying operation is possible, “no more copy” specifying that data hasbeen copied from the above “one copy” data, or “never copy” specifyingthat copying cannot be permitted. The reproducing device or therecording device, which has detected this copyright control information,limits reproduction or recording on the picture or music data.

On the optical disc D, there is recorded the media type information ofthis optical disc D, along with the above-mentioned picture data oraudio data. This media type information is the information specifyingwhether the optical disc is the read-only ROM disc or a recordable RAMdisc.

From this optical disc D, the above media type information as well asthe compressed picture or audio data is read out by the optical discdrive 20.

The optical disc drive 20 includes a first CSS encoder 21 for encryptingthe read-out compressed picture and speech data and a second CSS encoder22 for encrypting the read-out media type information.

The first CSS encoder 21 and the second CSS encoder 22 performencrypting by the so-called contents scramble system (CSS). The firstCSS encoder 21 and the second CSS encoder 22 perform encrypting usingdifferent algorithms or different encryption keys.

The optical disc drive 20 sends the encrypted compressed picture andspeech data and media type information to the bus 10 via an outputinterface, not shown. These different types of the information aretransmitted over this bus 10 to the data processing device 30.Therefore, picture data etc and the media type information, encrypted byrespective different encrypting systems, are transmitted over this bus10.

Meanwhile, if the compressed picture data etc and the media typeinformation are recorded on the optical disc D in respective differentencrypted state, it is possible for the optical disc drive 20 totransmit the information or data without encryption.

It is possible for the second CSS encoder 22 to encrypt not only themedia type information but also other control data. For example, thesecond CSS encoder 22 is able to encrypt the sub-code information forthe picture data etc, or the CGMS-D codes used for copyright protectioncontrol.

The data processing device 30 includes a first CSS decoder 31, a secondCSS decoder 32, an MPEG decoder 33, a media type decoder 34, a watermark(WM) detection/re-encoding unit 35, an output controller 36 and switches37, 38.

The first CSS decoder 31 is supplied with the encrypted and transmittedcompressed video and speech data via an interface, not shown. The firstCSS decoder 31 performs decryption in accordance with the algorithmmatched to the first CSS encoder 21 or using the matched encryption key.If decryption is not made using the correct decryption key, the ensuingprocessing cannot be effectuated. If decryption is done using thecorrect encryption key, the first CSS decoder 31 sends the picture dataand the speech data to the MPEG decoder 33.

The second CSS decoder 32 is supplied with the encrypted and transmittedmedia type information via an interface, not shown. This second CSSdecoder 32 performs decryption processing by an algorithm matched tothat of the second CSS encoder 22 and using the matched encryption key.If decryption is not made using the correct decryption key, the ensuingprocessing cannot be effectuated. If decryption is done using thecorrect encryption key, the second CSS decoder 32 sends the media typeinformation to the media type decoder 34.

The first CSS decoder 31 and the second CSS decoder 32 performencryption using different algorithms or different encryption keys in acorresponding manner to the first and second CSS encoders 21 and 22,respectively. Thus, if decryption cannot be effectuated in one of thefirst or second CSS decoders 31, 32, outputting is halted in itsentirety so that no ensuing processing can be performed.

The MPEG decoder 33 expands the compressed picture and audio data. Theexpanded picture data is sent to the watermark (WM)detection/re-encoding unit 35. The expanded speech data is outputted tooutside via switch 37.

The medium type decoder decodes the media type information supplied fromthe second CSS decoder 32to detect the information on whether theoptical disc D reproduced by the optical disc drive 20 is the ROM discor the RAM disc to send the detected information to the outputcontroller 37.

The watermark (WM) detection/re-encoding unit 35 detects the copyrightcontrol information superimposed on the picture data by watermarkprocessing. The detected copyright control information specifies one of“copy free”, “one copy”, “no more copy” or “never copy”, as describedabove. The watermark (WM) detection/re-encoding unit 35 sends thedetected copyright control information to the output controller 36. If,as a result of the detection of the copyright control information thewatermark (WM) detection/re-encoding unit 35 detects “one copy”, itre-encodes the copyright control information superimposed on the picturedata, using watermark processing, for changing “one copy” to “no morecopy”, to output the re-encoded copyright control information to outsidevia switch 38. If, as a result of the detection of the copyright controlinformation the watermark (WM) detection/re-encoding unit 35 detects thecopyright control information other than “one copy”, it outputs thedetected copyright control information to outside via switch 38 withoutdoing re-encoding.

The output controller 36 performs on/off control of the switches 37, 38based on the information sent from the media type decoder 34 and fromthe watermark (WM) detection/re-encoding unit 35. Specifically, if theoptical disc D is the ROM disc and the copyright control information isthe “no more copy”, and if the optical disc D is the RAM disc and thecopyright control information is “one copy”, the output controller 36assumes that the data recorded on the optical disc D has been copiedillicitly and performs control to turn the switches 37, 38 off.

The above-described optical disc reproducing device 1 of the firstembodiment of the present invention encrypts the media type informationas control data, and the picture and speech data, using respectivedifferent systems. Thus, with the present optical disc reproducingdevice 1, since the two types of data need to be decrypted, illicitduplication or reproduction cannot be made if one of the two types ofdata is attacked, thus improving the security.

Referring to FIG. 5, the second embodiment of the optical discreproducing device is explained.

In the following explanation of the second embodiment of the opticaldisc reproducing device, the parts or components which are the same asthose of the first embodiment are depicted by the same referencenumerals and are not explained specifically. The same applies for thethird and fourth embodiments of the optical disc reproducing device.

An optical disc reproducing device 2 includes an optical disc drive 20,for reading out picture or speech data recorded on the optical disc D, adata processing device 40 for doing data processing on picture data etcread out from the optical disc drive 20, and a bus 10 forinterconnecting the optical disc drive 20 and the data processing device40.

In a data area of the optical disc D, picture data for moving and stillpictures and speech data for music or speech are compressed inaccordance with the MPEG system and recorded in this compressed form. Onthe compressed picture data, there is superimposed the copyright controlinformation by watermark processing in its elementary stream state.Thus, in detecting the copyright control information, the copyrightcontrol information needs to be detected prior to MPEG expansion.

The optical disc drive 20 includes a first CSS encoder 21 for encryptingthe read-out compressed picture and speech data and a second CSS encoder22 for encrypting the read-out media type information.

The optical disc drive 20 sends the encrypted compressed picture andspeech data and media type information to the bus 10 via an outputinterface, not shown. These different types of the information aretransmitted over this bus 10 to the data processing device 40.Therefore, picture data etc and the media type information, encrypted byrespective different encrypting systems, are transmitted over this bus10.

The data processing device 40 includes a first CSS decoder 31, a secondCSS decoder 32, an MPEG decoder 33, a media type decoder 34, a watermark(WM) detection/re-encoding unit 42, an output controller 36 and switches37, 38.

The first CSS decoder 31 is supplied with the compressed video andspeech data, transmitted in an encrypted form, via an interface, notshown. The first CSS decoder 31 performs decryption in accordance withthe algorithm matched to the first CSS encoder 21 or using the matchedencryption key. If decryption is not made using the correct decryptionkey, the ensuing processing cannot be effectuated. If decryption is doneusing the correct encryption key, the first CSS decoder 31 sends thepicture data and the speech data to the MPEG decoder 33 via switch 41on/off controlled by the output controller 36. The first CSS decoder 31also sends the picture data and speech data to the watermark (WM)detection/re-encoding unit 42.

The second CSS decoder 32 is fed with encrypted and transmitted mediatype information via an input interface, not shown. This second CSSdecoder 32 performs decryption by an algorithm matched to that of thesecond CSS encoder 22 and using matched encryption keys. If decryptionis not made using the correct decryption key, the ensuing processingcannot be effectuated. If decryption is done using the correctencryption key, the second CSS decoder 32 sends the media typeinformation to the media type decoder 34.

The first and second CSS decoders 31, 32 effectuate encryption byemploying different algorithms or different encryption keys inassociation with the first and second CSS encoders 21, 22. Therefore, ifdecryption cannot be done by one of the first and second CSS decoders31, 32, outputting is halted so as to inhibit the ensuing operations.

The MPEG decoder 33 expands the compressed picture and speech data. Theexpanded picture and speech data are outputted to outside.

The watermark (WM) detection/re-encoding unit 42 detects the copyrightcontrol information superimposed by watermark processing on the picturedata. This watermark (WM) detection/re-encoding unit 42 detects thecopyright control information in the form of an elementary streamcompressed in accordance with the MPEG system. If, as a result ofdetection of the copyright control information, “one copy” is detected,the watermark (WM) detection/re-encoding unit 42 re-encodes thecopyright control information superimposed on the picture data bywatermark processing to change “one copy” to “no more copy”. Thewatermark (WM) detection/re-encoding unit 42 then sends the re-encodedcopyright control information to the MPEG decoder 33. If, as a result ofdetection of the copyright control information, the copyright controlinformation other than “one copy” is detected, the watermark (WM)detection/re-encoding unit 42 sends the detected copyright controlinformation to the MPEG decoder 33 without doing re-encoding.

The output controller 36 controls the switch to its on or off states,based on the information supplied from the media type decoder 34 and thewatermark (WM) detection/re-encoding unit 42.

The above-described optical disc reproducing device 2 of the secondembodiment of the present invention encrypts the media type informationas control data and the picture and speech data using different systems.Thus, with the present optical disc reproducing device 2, since the twotypes of data need to be decrypted, illicit duplication or reproductioncannot be made if one of the two types of data is attacked, thusimproving the security. Moreover, with the present optical discreproducing device 2, the playback output for copyright control ishalted to perform copyright control before supplying the copyrightcontrol information to the MPEG decoder 33, reproduction limitation andrecording limitation for copyright protection can be achieved withhigher security.

Referring to FIG. 6, the second embodiment of the optical discreproducing device is explained.

An optical disc reproducing device 3 of the present third embodimentincludes an optical disc drive 50, for reading out picture or speechdata recorded on the optical disc D, a data processing device 60 fordoing data processing on picture data etc read out from the optical discdrive 50, and buses 10, 11 for interconnecting the optical disc drive 50and the data processing device 60.

In a data area of the optical disc D, picture data for moving and stillpictures and speech data for music or speech are compressed inaccordance with the MPEG system and recorded in this compressed form. Onthe picture data, the copyright control information is superimposed bythe above-described watermark processing.

The optical disc drive 50 includes a first CSS encoder 21 for encryptingthe compressed picture data, compressed audio data and media typeinformation, as read out, and a third CSS decoder 51 for decrypting thecontrol data transmitted from the data processing device 60.

The first CSS encoder 21 encrypts the compressed picture data,compressed audio data and media type information by so-called CSS.

To the third CSS decoder 51, control data for copyright control is sentfrom the data processing device 60 via an input interface, not shown.This control data is already encrypted using algorithms or encryptionkeys different from those for the picture data etc and the media typeinformation. This third CSS decoder 51 performs corresponding decryptingoperations to halt the optical disc reproducing operation, based on thecontrol data contents.

The optical disc drive 50 sends the encrypted compressed picture data,compressed audio data and media type information to the bus 10 via anoutput interface, not shown. These data or the information aretransmitted over the bus 10 to the data processing device 60. Theoptical disc drive 50 also acquires the encrypted control data forhalting the optical disc D from the data processing device 60 over thebus 11. Thus, the picture data etc, media type information and thecontrol data, encrypted using respective different encoding systems, aretransmitted over the buses 10 and 11.

The data processing device 60 includes a first CSS decoder 31, an MPEGdecoder 33, a media type decoder 34, a watermark (WM)detection/re-encoding unit 35, an output controller 36 and a third CSSencoder 61.

The first CSS decoder 31 is supplied with compressed picture data,compressed audio data and media type information, transmitted followingthe encryption, and decrypts the data or the information using pre-setencryption keys. If the decryption is done using the correct encryptionkey, the picture and speech data are sent to the MPEG decoder 33, whilethe media type information is sent to the media type decoder 34.

The MPEG decoder 33 expands the compressed picture and audio data. Theexpanded picture data is sent to the watermark (WM)detection/re-encoding unit 35. The expanded speech data is outputted tooutside.

The media type decoder 34 decodes the media type information suppliedfrom the first CSS decoder 31 to detect the information as to whetherthe optical disc D being reproduced by the optical disc drive 50 is theROM disc or the RAM disc to send the detected information to the outputcontroller 36.

The watermark (WM) detection/re-encoding unit 35 detects the copyrightcontrol information superimposed by watermark processing on the picturedata. The detected copyright control information specifies one of “copyfree”, “one copy”, “no more copy” or “never copy”, as described above.The watermark (WM) detection/re-encoding unit 35 sends the detectedcopyright control information to the output controller 36. If, as aresult of the detection of the copyright control information thewatermark (WM) detection/re-encoding unit 35 detects “one copy”, itre-encodes the copyright control information superimposed on the picturedata, using watermark processing, for changing “one copy” to “no morecopy”, to output the re-encoded copyright control information to outsidevia switch 38. If, as a result of the detection of the copyright controlinformation the watermark (WM) detection/re-encoding unit 35 detects thecopyright control information other than “one copy”, it outputs thedetected copyright control information to outside via switch 38 withoutdoing re-encoding.

The output controller 36 performs control for halting the reproductionof the optical disc drive 50 based on the information sent from themedia type decoder 34 and from the watermark (WM) detection/re-encodingunit 35. Specifically, if the optical disc D is the ROM disc and thecopyright control information is the “no more copy”, and if the opticaldisc D is the RAM disc and the copyright control information is “onecopy”, the output controller 36 assumes that the data recorded on theoptical disc D has been copied illicitly and performs control to haltthe reproducing operation for the optical disc drive 50.

The third CSS encoder 61 encrypts the control data, using the algorithmor encryption keys different from those used for the picture data etcand the media type information. The third CSS encoder 61 sends theencrypted control data via an output interface, not shown, to the bus11, and thence sends the data to the optical disc drive 50. Thus, thecontrol data, encrypted in accordance with the encrypting systemdifferent from that for data transmitted over bus 10, is transmittedover this bus 11.

To the third CSS decoder 51 of the optical disc drive 50, the controldata encrypted and transmitted by the third CSS decoder 51 is enteredvia an input interface, not shown. This third CSS decoder 51 decryptsthe data using an algorithm or encryption keys matched to that of thethird CSS encoder 61. If the correct encryption keys are not used fordecryption, the ensuing processing is not effectuated, so that thereproducing operation of the optical disc is halted. If the correctencryption keys are used for decryption, but the output controller 36verifies that the data recorded on the optical disc D has beenduplicated illicitly, the third CSS decoder 51 halts the reproducingoperation of the optical disc D based on the supplied control data.

With the optical disc reproducing device 3 of the third embodiment, thedata transmitted between the optical disc drive 50 and the dataprocessing device 60 is encrypted using respective different systems.Thus, with the present optical disc reproducing device 3, since the twotypes of data need to be decrypted, illicit duplication or reproductioncannot be made if one of the two types of data is attacked, thusimproving the security. Moreover, with the present optical discreproducing device, since the playback output for copyright control ishalted on the optical disc drive 50 prior to transmission of picturedata etc over the bus 10, playback limitation and recording limitationfor copyright protection can be achieved with higher security.

Referring to FIG. 7, the fourth embodiment of the optical discreproducing device is explained.

An optical disc reproducing device 4 of the present fourth embodimentincludes an optical disc drive 50, for reading out picture or speechdata recorded on the optical disc D, a data processing device 70 fordoing data processing on picture data etc read out from the optical discdrive 50, and buses 10, 11 for interconnecting the optical disc drive 50and the data processing device 70.

In a data area of the optical disc D, picture data for moving and stillpictures and speech data for music or speech are compressed inaccordance with the MPEG system and recorded in this compressed form. Onthe compressed picture data, in a state of its elementary stream, thereis superimposed the copyright control information by watermarkprocessing. Thus, for detecting this copyright control information, itis necessary to perform detection prior to MPEG expansion.

The optical disc drive 20 includes a first CSS encoder 21, forencrypting the compressed picture data and the compressed speech data,as read out, a second CSS encoder 22 for encrypting the read-out mediatype information and a third CSS decoder 51 for decrypting the controldata transmitted from the data processing device 70.

The third CSS decoder 51 is supplied with control data for copyrightcontrol from the data processing device 70 via an input interface, notshown. This control data is encrypted using an algorithm or encryptionkeys different from those for the picture data etc or the media typeinformation. This third CSS decoder 51 performs corresponding decryptionto halt the playback operation for the optical disc D based on thecontents of the control data.

The optical disc drive 50 sends the encrypted compressed picture andspeech data and the encrypted media type information to the bus 10 viaan output interface, not shown. These data and information aretransmitted from this bus 10 to the data processing device 70. Theoptical disc drive 50 also acquires the encrypted control data forhalting the optical disc D from the data processing device 70 over thebus 10. Thus, the picture data etc and the media type informationencrypted by respective different encrypting systems are transmitted onthis bus 10, while control data encrypted by an encryption systemdifferent form that transmitted on the bus 10 is transmitted on the bus11.

The data processing device 70 includes a first CSS decoder 31, a secondCSS decoder 32, a media type decoder 34, a watermark (WM)detection/re-encoding unit 42, an output controller 36 and a third CSSencoder 61.

The first CSS decoder 31 is supplied with compressed picture data andcompressed speech data, encrypted and transmitted in this form, via aninput interface, not shown, and decrypts the data by an algorithm andthe encryption key matched to those for the first CSS encoder 21. If thedecryption is not done using the correct encryption key, the ensuingprocessing cannot be executed. If the decryption is done using thecorrect encryption key, the first CSS decoder 31 sends the picture dataand the speech data to the watermark (WM) detection/re-encoding unit 42.

The second CSS decoder 32 is supplied with compressed picture data andcompressed speech data, encrypted and transmitted in this form, via aninput interface, not shown, and decrypts the data by an algorithm andthe encryption key matched to those for the second CSS encoder 22. Ifthe decryption is not done using the correct encryption key, the ensuingprocessing cannot be executed. If the decryption is done using thecorrect encryption key, the second CSS decoder 32 sends the media typwinformation y to the media type decoder 34.

The MPEG decoder 33 expands the compressed picture and speech data. Theexpanded picture and speech data are outputted to outside.

The watermark (WM) detection/re-encoding unit 42 detects the copyrightcontrol information superimposed by watermark processing. The watermark(WM) detection/re-encoding unit 42 detects the copyright controlinformation in the state of an elementary stream compressed inaccordance with the MPEG system. The watermark (WM)detection/re-encoding unit 42 sends the detected copyright controlinformation to the output controller 36. If, as a result of thedetection of the copyright control information, the watermark (WM)detection/re-encoding unit 42 detects “one copy”, it re-encodes thecopyright control information superimposed on the picture data, usingwatermark processing, for changing “one copy” to “no more copy”, tooutput the re-encoded copyright control information to the MPEG decoder33. If, as a result of the detection of the copyright controlinformation, the watermark (WM) detection/re-encoding unit 42 detectsthe copyright control information other than “one copy”, it outputs thedetected copyright control information to outside via switch 38 withoutdoing re-encoding.

The output controller 36 performs control for halting the reproductionof the optical disc drive 50 based on the information sent from themedia type decoder 34 and from the watermark (WM) detection/re-encodingunit 35. Specifically, if the optical disc D is the ROM disc and thecopyright control information is the “no more copy”, and if the opticaldisc D is the RAM disc and the copyright control information is “onecopy”, the output controller 36 assumes that the data recorded on theoptical disc D has been copied illicitly and performs control to haltthe reproducing operation for the optical disc drive 50. The outputcontroller 36 sends this control data to the third CSS encoder 61.

The third CSS encoder 61 encrypts the control data, using the algorithmor encryption keys different from those used for the picture data etcand from the media type information. The third CSS encoder 61 sends theencrypted control data via an output interface, not shown, to the bus11, and thence sends the data to the optical disc drive 50. Thus, thecontrol data, encrypted in accordance with the encrypting systemdifferent from that for data transmitted over bus 10, is transmittedover this bus 11. Therefore, control data encrypted by an encryptionsystem different from that for data transmitted on the bus 10 istransmitted on the bus 10.

To the third CSS decoder 51 of the optical disc drive 50, the controldata encrypted and transmitted by the third CSS decoder 51, is enteredvia an input interface, not shown. This third CSS decoder 51 decryptsthe data using an algorithm or encryption keys matched to those of thethird CSS encoder 61. If the correct encryption keys are not used fordecryption, the ensuing processing is not effectuated, so that thereproducing operation of the optical disc is halted. If the correctencryption keys are used for decryption, but the output controller 36verifies that the data recorded on the optical disc D has beenduplicated illicitly, the third CSS decoder 51 halts the reproducingoperation of the optical disc D based on the supplied control data.

With the optical disc reproducing device 3 of the third embodiment, thedata transmitted between the optical disc drive 50 and the dataprocessing device 60 is encrypted using respective different systems forcontrol data and picture data. Thus, with the present optical discreproducing device 3, since the two types of data need to be decrypted,illicit duplication or reproduction cannot be made if one of the twotypes of data is attacked, thus improving the security. Moreover, withthe present optical disc reproducing device, since the playback outputfor copyright control is halted on the optical disc drive 50 prior totransmission of picture data etc over the bus 10, playback limitationand recording limitation for copyright protection can be in the achievedwith higher security.

In the above explanation of the first to fourth embodiments, the presentinvention is retained to be directed to a reproducing device for anoptical disc applied to, for example, a personal computer. The presentinvention, however, is not applied to this configuration and may also beapplied to a system employing the Internet or the digital broadcastingsatellite as a transmission medium. In this case, there is constructedsuch a system in which the reproducing device side operates as a serverand the data processing device side operates as a client, and in whichencryption is performed on the picture data etc and control datatherefor being transmitted. That is, high security can be achievedagainst unauthorized duplication in the system employing the Internetand the digital satellite broadcast.

What is claimed is:
 1. A data reproducing apparatus for reproducingaudio visual data, comprising: reproducing means for reproducing firstand second data recorded on a recording medium; first encryption meansfor performing first encryption processing on said first data reproducedfrom said recording medium by said reproducing means, said first datacomprising medium type information; second encryption means forperforming second encryption processing different from said firstencryption processing on said second data reproduced from said recordingmedium by said reproducing means, said second data comprising copyrightcontrol information, and said second encryption processing comprisingwatermark processing to superimpose said second data on said audiovisual data; and transmission means for transmitting the data encryptedby said first encryption means and the second encryption means; whereinsaid copyright control information and said medium type information areused to control copyright control processing.
 2. The data reproducingapparatus according to claim 1 wherein said reproducing means reproducessaid audio visual data.
 3. The data reproducing apparatus according toclaim 2 wherein the copyright control information is superimposed bywatermark processing on said audio visual data after being reproduced aspart of said audio visual data.
 4. A data reproducing apparatus forreproducing audio visual data, comprising: reproducing means forreproducing first and second data recorded on a recording medium;encryption means for encrypting the first data reproduced by saidreproducing means comprising medium-type information in accordance witha first encryption processing and for encrypting the second datareproduced by said reproducing means, comprising copyright controlinformation relevant at least to copyright control processing of saidaudio visual data, in accordance with a superimposing watermark process;transmission means for transmitting said first and second data encryptedby said encrypting means to an external signal processing device;reception means for receiving playback control data transmitted fromsaid external signal processing device, said playback control datacomprising said data transmitted by said transmission means encrypted ina manner different from said encrypting by said encrypting means andprocessed with copyright control processing; decrypting means forperforming decryption processing matched to encryption of said playbackcontrol data received by said reception means; and control means forcontrolling the playback processing of said reproducing means based onsaid playback control data decrypted by said decrypting means.
 5. Thedata reproducing apparatus according to claim 4 wherein said reproducingmeans reproduces said audio visual data.
 6. The data reproducingapparatus according to claim 5 wherein the copyright control informationis superimposed by watermark processing on said audio visual data afterbeing reproduced as part of said audio visual data.
 7. The datareproducing apparatus according to claim 4 wherein said encryption meansincludes first encrypting means for performing first encryptionprocessing on said first data reproduced by said reproducing means and asecond encrypting means for performing second encryption processingdifferent from said first encryption processing on at least saidcopyright control information of said second reproduced data relevant tocopyright control processing; said reception means receiving playbackcontrol data encrypted in a manner different from both said firstencryption processing and said second encryption processing.
 8. The datareproducing apparatus according to claim 7 wherein said reproducingmeans reproduces said audio visual data.
 9. The data reproducingapparatus according to claim 8 wherein the copyright control informationis superimposed by watermark processing on said audio visual data afterbeing reproduced as part of said audio visual data.
 10. A dataprocessing apparatus for reproducing audio visual data, comprising:reception means for receiving first data processed in accordance withfirst encryption processing and second data superimposed on said audiovisual data in accordance with watermark processing different from saidfirst encryption processing, comprising copyright control information atleast relevant to copyright control processing of said audio visualdata, said first and second data being transmitted from an externaldevice; first decrypting means for performing first decryptionprocessing, matched to said first encryption processing, on said firstdata received by said reception means, said first data comprisingmedia-type information; second decrypting means for performing seconddecryption processing, matched to said watermark processing, on saidsecond data received by said reception means; outputting means foroutputting data decrypted by said second decrypting means; and controlmeans for performing copyright control processing of said data output bysaid outputting means, based on at least the first data decrypted by thefirst decryption means and the second data, comprising copyright controlinformation, decrypted by said second decrypting means, for controllingoutputting processing of said outputting means.
 11. The data processingapparatus according to claim 10 wherein said reception means receivessaid audio visual data and said copyright control information.
 12. Thedata processing apparatus according to claim 11 wherein the copyrightcontrol information is superimposed by watermark processing on saidaudio visual data; copyright control information detecting means beingprovided for detecting the copyright control information from the seconddata decrypted by said second decrypting means; said control meansperforming output control of said data output by said outputting meansbased on said copyright control information detected by said copyrightcontrol information detection means and based on said medium-typeinformation decrypted by said first decrypting means.
 13. A dataprocessing apparatus for reproducing audio visual data, comprising:reception means for receiving first data comprising medium-typeinformation and second data, comprising copyright control information atleast relevant to copyright control processing of said audio visualdata, said first data being encrypted in accordance with a firstencryption process and the second data being superimposed on said audiovisual data in accordance with watermark processing, said first andsecond data being transmitted in this encrypted form from an externaldevice; decrypting means for performing matched decryption processing onsaid first data and said second data received by said reception means;outputting means for outputting data decrypted by said decrypting means;control means for performing copyright control processing of said dataoutput by said outputting means, based on at least the first data andsecond data decrypted by said decrypting means, for generatingtransmission control data for controlling transmission processing ofsaid data transmitted from said external device; encrypting means forperforming encryption processing on said transmission control datagenerated by said control means, said encryption processing beingdifferent from that performed on the first and second data received bysaid reception means; and transmitting means for transmitting thetransmission control data encrypted by said encrypting means to saidexternal device.
 14. The data processing apparatus according to claim 13wherein said reception means receives said audio visual data and thefirst and second data for the copyright control processing thereof. 15.The data processing apparatus according to claim 14 wherein thecopyright control information is superimposed by watermark processing onsaid audio visual data; copyright control information detection meansbeing provided for detecting the copyright control information from thefirst and second data decrypted by said decrypting means received viasaid reception means; said control means performing copyright controlprocessing controlling of said data output by said outputting means,based on said copyright control information detected by said copyrightcontrol information detection means and based on said medium-typeinformation decrypted by said decrypting means, for generatingtransmission control data controlling transmission processing of datatransmitted from said external device.
 16. The data processing apparatusaccording to claim 13 wherein said reception means receiving said firstdata processed with first encryption processing and said second data,comprising copyright control information at least relevant to copyrightcontrol processing of said audio visual data and which is superimposedin accordance with watermark processing, said first data and the seconddata being transmitted from an external device; said decrypting meansincluding first decrypting means for performing decryption processing,matched to said first encryption processing, on said first data receivedby said reception means, and second decrypting means for performingdecryption processing, matched to said watermark processing, on saidsecond data received by said reception means; and said encrypting meansperforms encryption processing on the transmission control data, saidencrypting processing being different from both said first encryptionprocessing and said watermark processing.
 17. The data processingapparatus according to claim 16 wherein said reception means receivessaid audio visual data and said copyright control information for thecopyright control processing thereof.
 18. The data processing apparatusaccording to claim 17 wherein the copyright control information issuperimposed by watermark processing on said audio visual data;copyright control information detection means being provided fordetecting the copyright control information from the second datadecrypted by said second decrypting means; said control means performingoutput control processing of said data output by said outputting meansbased on said copyright control information detected by said copyrightcontrol information detection means and based on said medium-typeinformation decrypted by said first decrypting means for generatingtransmission control data controlling the transmission processing ofdata transmitted from said external device.
 19. A data transmissionsystem comprising a data reproducing apparatus and a data processingapparatus, in which audio visual data reproduced from a recording mediumby said data reproducing apparatus is transmitted to said dataprocessing apparatus, the transmitted data being processed in apredetermined manner by said data processing apparatus and in which theprocessed data is then output, said data reproducing apparatus includingreproducing means for reproducing first and second data recorded on arecording medium, first encryption means for performing first encryptionprocessing on said first data reproduced from said recording medium bysaid reproducing means, said first data comprising medium-typeinformation, second encryption means for performing second encryptionprocessing different from said first encryption processing on saidsecond data reproduced from said recording medium by said reproducingmeans, said second data comprising copyright control information, andsaid second encryption processing comprising watermark processing tosuperimpose said second data on said audio visual data, and transmissionmeans for transmitting the data encrypted by said first encryption meansand the second encryption means; said data processing apparatusincluding reception means for receiving first data processed with saidfirst encryption processing and second data superimposed on said audiovisual data in accordance with said watermark processing different fromsaid first encryption processing, comprising copyright controlinformation at least relevant to copyright control processing of saidaudio visual data, said first and second data being transmitted from anexternal device, first decrypting means for performing first decryptionprocessing, matched to said first encryption processing, on said firstdata received by said reception means, second decrypting means forperforming second decryption processing, matched to said watermarkprocessing, on said second data received by said reception means,outputting means for outputting data decrypted by said second decryptingmeans, and control means for performing copyright control processing ofsaid data output by said outputting means, based on at least the firstdata decrypted by the first decryption means and the second data,comprising copyright control information decrypted by said seconddecrypting means, for controlling outputting processing of saidoutputting means.
 20. The data transmission system according to claim 19wherein said transmission means and the reception means transmit andreceive said audio visual data and said copyright control informationfor copyright control processing thereof, respectively.
 21. The datatransmission system according to claim 20 wherein the copyright controlinformation is superimposed by watermark processing on said audio visualdata; copyright control information detection means being provided inthe data processing apparatus for detecting the copyright controlinformation from the second data decrypted by said second decryptingmeans, said control means controlling the output of data by saidoutputting means based on said copyright control information detected bysaid copyright control information detection means and based on saidmedium-type information decrypted by said first decrypting means.
 22. Adata transmission system comprising a data reproducing apparatus and adata processing apparatus, in which audio visual data reproduced from arecording medium by said data reproducing apparatus is transmitted tosaid data processing apparatus, the transmitted audio visual data isprocessed in a predetermined manner by said data processing apparatus,and in which the processed audio visual data is output, said datareproducing apparatus including reproducing means for reproducing firstand second data recorded on a recording medium, encryption means forencrypting, in accordance with a first encryption processing, the firstdata comprising media-type information reproduced by said reproducingmeans and for encrypting the second data reproduced by said reproducingmeans in accordance with a superimposing processing, said second datacomprising copyright control information relevant to at least copyrightcontrol processing of said audio visual data, transmission means fortransmitting said first and second data encrypted by said encryptingmeans to an external signal processing device, reception means forreceiving playback control data transmitted from said external signalprocessing device, said playback control data being said datatransmitted by said transmission means, said transmitted data beingprocessed with copyright control processing, decrypting means forperforming decryption processing matched to the encryption of saidplayback control data received by said reception means, and controlmeans for controlling the playback processing of said reproducing meansbased on said playback control data decrypted by said decrypting means;said data processing device including reception means for receiving saidfirst data comprising media-type information and said second data,comprising copyright control information relevant to at least copyrightcontrol processing of said audio visual data, said first data beingencrypted in accordance with a first encryption process and the seconddata being superimposed on said audio visual data in accordance withwatermark processing, said first and second data being transmitted inthis encrypted form from an external device, decrypting means forperforming matched decryption processing on said first and said seconddata received by said reception means, outputting means for outputtingdata decrypted by said decrypting means, control means for performingcopyright control processing of said data output by said outputtingmeans, based on at least the first data and the second data decrypted bysaid decrypting means, for generating transmission control data forcontrolling the transmission processing of said data transmitted fromsaid external device, encrypting means for performing encryptionprocessing on said transmission control data generated by said controlmeans, said encryption processing being different from the encryptionprocessing performed on the first and second data received by saidreception means, and transmitting means for transmitting thetransmission control data encrypted by said encrypting means to saidexternal device.
 23. The data transmission system according to claim 22wherein said transmission means and the reception means transmit andreceive said audio visual data and said copyright control informationfor copyright control processing thereof, respectively.
 24. The datatransmission system according to claim 23 wherein the copyright controlinformation is superimposed by watermark processing on said audio visualdata; copyright control information detection means being provided insaid data processing device for detecting the copyright controlinformation from first and second data decrypted by said firstdecrypting means received via said reception means; and said controlmeans performing copyright control processing of said data output bysaid outputting means, based on said copyright control informationdetected by said copyright control information detection means and basedon said medium-type information decrypted by said decrypting means, toperform copyright control processing of said data output by saidoutputting means to control data transmitted from said data reproducingmeans.
 25. The data transmission system according to claim 22 wherein insaid data reproducing device, said encryption means includes firstencrypting means for performing first encryption processing on saidfirst data reproduced by said reproducing means and a second encryptingmeans for performing second encryption processing different from saidfirst encryption processing on at least copyright control information ofsaid reproduced data relevant to copyright control processing; andwherein in said data processing device, said decrypting means includesfirst decrypting means for performing first decryption processing,matched to said first encryption processing, on said data received bysaid reception means, and second decrypting means for performing seconddecryption processing, matched to said second encryption processing, onsaid data received by said reception means, said encrypting meansperforming encryption processing different from both the firstdecryption processing and the second decryption processing on thetransmission control data.
 26. The data transmission system according toclaim 25 wherein said transmission means and said reception meanstransmit and receive said audio visual data and said copyright controlinformation for copyright control processing thereof, respectively. 27.The data transmission system according to claim 26 wherein the copyrightcontrol information is superimposed by watermark processing on saidaudio visual data; and copyright control information detection meansbeing provided in said data reproducing device for detecting thecopyright control information from the audio visual data decrypted bysaid second decrypting means, said control means performing outputcontrol processing of said data output by said outputting means, basedon said copyright control information detected by said copyright controlinformation detection means and based on said medium-type informationdecrypted by said first decrypting means to generate transmissioncontrol data controlling data transmitted from said data reproducingmeans.
 28. A data reproducing method for reproducing audio visual datacomprising the steps of: reproducing first and second data recorded on arecording medium; performing first encryption processing on the firstdata reproduced, said first data comprising medium-type information;performing second encryption processing, different from said firstencryption processing, on said second data, said second data comprisingcopyright control information, and said second encryption processingcomprising watermark processing to superimpose said second data on saidaudio visual data; and transmitting the encrypted data and encryptedcontrol data; wherein said copyright control information and saidmedium-type information are used to control copyright controlprocessing.
 29. The data reproducing method according to claim 28wherein said audio visual data is reproduced from said recording medium.30. The data reproducing apparatus according to claim 29 wherein thecopyright control information is superimposed by watermark processing onsaid audio visual data after being reproduced as part of said audiovisual data.
 31. A data reproducing method for reproducing audio visualdata comprising the steps of: reproducing first and second data recordedon a recording medium; encrypting the reproduced first data comprisingmedium-type information in accordance with a first encryption processingfor encrypting the reproduced second data, comprising copyright andcontrol information relevant to at least the copyright controlprocessing of said audio visual data in accordance with a superimposingwatermark process; transmitting the encrypted first and second data toan external signal processing device; receiving playback control datatransmitted from said external signal processing device, said playbackcontrol data comprising the data transmitted to said external signalprocessing device following copyright control processing and subsequentencryption processing different from the prior encryption processingperformed on said control data; performing decryption processing on thereceived playback control data matched to the encryption processing forthe received playback control data; and controlling the playbackprocessing based on the decrypted playback control data.
 32. The datareproducing method according to claim 31 wherein said audio visual datais reproduced from said recording medium.
 33. The data reproducingapparatus according to claim 32 wherein the copyright controlinformation is superimposed by watermark processing on said audio visualdata after being reproduced as part of said audio visual data.
 34. Adata reproducing method for reproducing audio visual data comprising thesteps of: reproducing first and second data from a storage device;performing first encryption processing on the reproduced first datacomprising medium-type information; performing second encryptionprocessing, different from said first encryption processing, on thereproduced second data, comprising copyright control informationrelevant to copyright control processing of the reproduced audio visualdata; and receiving playback control data subjected to encryptionprocessing different from both the first encryption processing and thesecond encryption processing.
 35. The data reproducing method accordingto claim 34 wherein said audio visual data is reproduced from saidrecording medium.
 36. The data reproducing apparatus according to claim35 wherein the copyright control information is superimposed bywatermark processing on said audio visual data after being reproduced aspart of said audio visual data.
 37. A data processing method forreproducing audio visual data comprising the steps of: receiving firstdata subjected to first encryption processing and second datasuperimposed on said audio visual data in accordance with watermarkprocessing different from said first encryption processing, comprisingcopyright control information at least relevant to copyright controlprocessing of said audio visual data, said first and second data beingtransmitted from an external device; performing first decryptionprocessing matched to said first encryption processing on the receivedfirst data, said first data comprising medium-type information;performing second decryption processing matched to said watermarkprocessing on the received second data; performing at least copyrightcontrol processing of said audio visual data based on said first andsecond data; and outputting the audio visual data in accordance withsaid copyright control processing.
 38. The data processing methodaccording to claim 37 wherein said audio visual data and the first andsecond data relevant to copyright control processing thereof arereceived together.
 39. The data processing method according to claim 38wherein the copyright control information is superimposed by watermarkprocessing on said audio visual data; the copyright control informationis detected from the second data decrypted in accordance with saidsecond decryption processing; and said audio visual data isoutputting-controlled based on the detected copyright controlinformation and on the decrypted medium-type information.
 40. A dataprocessing method for reproducing audio visual data comprising the stepsof: receiving first data comprising medium-type information and seconddata, comprising copyright control information at least relevant tocopyright control processing of said audio visual data, said first databeing encrypted in accordance with a first encryption processing and thesecond data being superimposed on said audio visual data in accordancewith watermark processing, said first and second data being transmittedin this encrypted form from an external device; performing matcheddecryption processing on the received first data and second data;outputting the decrypted data; performing copyright control processingon said output data, based at least in part on the decrypted first andsecond data, to generate transmission control data for controllingtransmission of data from said external device; performing encryptionprocessing, different from that performed on the first and second data,on the generated transmission control data; and transmitting theencrypted transmission control data to said external device.
 41. Thedata processing method according to claim 40 wherein said audio visualdata and the first and second data relevant to copyright controlprocessing are received together.
 42. The data processing methodaccording to claim 41 wherein the copyright control information issuperimposed by watermark processing on said audio visual data; thecopyright control information is detected from the decrypted first andsecond data; and wherein copyright control processing is performed onthe output data based on the detected copyright control information andbased on said medium-type information.
 43. The data processing methodaccording to claim 40, further comprising the steps of: receiving saidfirst data subjected to first encryption processing and said seconddata, comprising copyright control information relevant to at leastcopyright control processing of said audio visual data and which issuperimposed in accordance with watermark processing, said first dataand said second data being transmitted from an external device;subjecting the received first data to first decryption processingmatched to said first encryption processing; subjecting the receivedsecond data to second decryption processing matched to said watermarkprocessing; and subjecting the transmitted control data to encryptionprocessing different from both the first encryption processing and thewatermark processing.
 44. The data processing method according to claim43, further comprising the step of: receiving said audio visual data andsaid copyright control information relevant to copyright controlprocessing together.
 45. The data processing method according to claim44 wherein the copyright control information is superimposed bywatermark processing on said audio video data; the copyright controlinformation is detected from the decrypted audio visual data, andwherein copyright control processing of said outputted data is performedbased on the detected copyright control information and the decryptedmedium-type information.
 46. A data transmission method in which atransmitting side transmits audio visual data reproduced from arecording medium via a transmission medium and in which a reception sideperforms pre-set processing on transmitted audio visual data to outputthe processed audio visual data, wherein the transmitting sidereproduces first and second data recorded on the recording medium, saidfirst data comprising medium-type information, processes the reproducedfirst data with first encryption, processes the reproduced second datawith second encryption different from said first encryption, said seconddata comprising copyright control information, and said secondencryption processing comprising watermark processing to superimposesaid second data on said audio visual data, and transmits the encryptedfirst and second data over a transmission medium; the reception sidereceives the transmitted first data and second data superimposed on saidaudio visual data, performs first decryption processing matched to saidfirst encryption processing on the received first data, performs seconddecryption processing matched to said second encryption processing onthe received second data, the decrypted first and second data beingoutput, and copyright control processing for the output data beingperformed based on at least the copyright control information subjectedto said second decryption processing.
 47. The data transmission methodaccording to claim 46 further comprising the step of: transmitting saidaudio visual data and said copyright control information relevant tocopyright control processing together.
 48. The data transmission methodaccording to claim 47 wherein the copyright control information issuperimposed by watermark processing on said audio visual data; andwherein the reception side detects the copyright control informationfrom decrypted second data and performs output control of said audiovisual data based on the detected copyright control information and thedecrypted medium-type information.
 49. A data transmission method inwhich a transmitting side transmits audio visual data reproduced from arecording medium via a transmission medium and in which a reception sideperforms pre-set processing on transmitted audio visual data to outputthe processed audio visual data, wherein the transmitting sidereproduces first and second data recorded on the recording medium,processes the reproduced first data in accordance with a firstencryption processing, said first data comprising medium-typeinformation and processing the reproduced second data in accordance witha superimposing process, said second data comprising copyright andcontrol information relevant to at least copyright control processing ofsaid audio visual data, transmits the encrypted first and second dataover a transmission medium to the reception side, receives encryptedplayback control data, performs decryption processing matched toencryption processing of the received playback control data, andcontrols playback processing based on the decrypted playback controldata; and wherein the reception side receives the transmitted first andsecond data, performs matched decryption processing on the receivedfirst and second data, outputs the decrypted data, performs copyrightcontrol processing of said output data based on at least the decryptedfirst and second data, generates transmission control data forcontrolling the transmission of data from the transmitting side,performs decryption processing on the generated transmission controldata different from that performed on the received first and seconddata, and transmits the encrypted transmission control data to thetransmitting side.
 50. The data transmission method according to claim49 further comprising the step of: transmitting said audio visual dataand said first and second data together.
 51. The data transmissionmethod according to claim 50 wherein the copyright control informationis superimposed by watermark processing on said audio visual data; andwherein the reception side detects the copyright control informationfrom the decrypted first and second data and performs copyright controlprocessing of the output data based on at least the detected copyrightcontrol information and the decrypted medium-type information togenerate transmission control data for controlling transmission of datafrom the transmitting side.
 52. The data transmitting method accordingto claim 49 wherein the transmitting side performs first encryptionprocessing on the reproduced first data, performs second encryptionprocessing different from the first encryption processing on thereproduced second data, and receives the encrypted playback control datafrom the receiving side; and wherein the reception side receives thetransmitted first and second data and the control data, performs firstdecryption processing matched to the first encryption processing on saidfirst data and second decryption processing matched to the secondencryption processing on the received second data, and decryption on thereceived playback control data corresponding to the encryptionprocessing thereof, respectively, and performs encryption processingdifferent from both the first encryption processing and the secondencryption processing on the transmission control data.
 53. The datatransmitting method according to claim 52 further comprising the stepsof: reproducing said audio visual data and said first and second datatogether.
 54. The data transmitting method according to claim 53 whereinthe copyright control information is superimposed by watermarkprocessing on said audio visual data; and wherein the reception sidedetects the copyright control information from decrypted first andsecond data and performs copyright control processing of the output databased on at least the detected copyright control information and thedecrypted medium-type information to generate transmission control datafor controlling transmission of data from the transmitting side.